Meanwhile, David Robertson had been waiting for the phone to ring. And waiting and waiting. It happened Thursday night, and Robertson -- the successor to the great Mariano Rivera -- made the transition seamless.

"It's just different when you call," Joe Girardi said. "Yankee managers have been calling down for a long time asking for Mo."

The last time Robertson appeared at Minute Maid Park, during the 2013 season finale, he was loudly booed for not being Rivera. Thursday night, you could hardly notice the difference. Robertson, pumping his own cut fastballs, retired the Astros in order -- but not before giving up a 390-foot fly ball to Matt Dominguez.

He also whiffed Alex Presley and got Jonathan Villar on a tapper to the mound. When the 4-2 win over the Astros was secure -- along with Robertson's first post-Mo save -- Mark Teixeira dropped the ball into the new closer's glove to keep.

We've talked about moving on from Rivera for what's seemed like years now. There's no point in calling Robertson his replacement. He's the Yankees' next closer, the one after the legendary Mo, and none of us, including Robertson himself, pretends this vacancy can just be filled, like finding another baby-sitter or accountant.

The job itself isn't new for Robertson. He did have eight saves in brief fill-in spots for Rivera. It's the title that's different. With Robertson taking the reins, we're not sure what exactly will follow. Is this the start of the Robertson Era? Or a period of post-Rivera angst for the Yankees?

We probably won't figure that out for a while. But it has to be nice to get that first save. At least that's what we assumed when Robertson was asked before the game if he was anxious about it.

"Not really,'' he said. "That thought really hadn't crossed my mind. I look at it as the same as last year. When the opportunity came and it was time for me to step in and get a hold, that's what I did. This is the same thing. It's just called a close.''

Robertson paused for a moment and corrected himself. "Or a save,'' he said, smiling. "Whatever. It's the same situation.''

We'll excuse Robertson for the slip, but now he has to get his terminology right. Maybe it was just the rust from sitting around since the team broke camp Saturday in Tampa.

The Yankees believe Robertson can make the transition from one of the game's best set-up men to an elite closer, even if they didn't hand him the job right away in the weeks after Rivera's retirement. Without a veteran Plan B in reserve, the Yankees are all in on Robertson.

"He's been in a lot of big pressure situations before,'' Girardi said. "Whether it's been the American League Championship Series, the World Series -- he's been in them. Hopefully, that helps him.''

Along with a few deep breaths when Robertson jogged in from the bullpen for that first time. Ask any closer: The adrenaline in that ninth inning is unlike any other spot. Factor in a new team, a new city, on Opening Day, and the levels can be off the chart.

Nathan, who signed a two-year, $20-million deal with the Tigers, imploded Wednesday in his first save chance at Comerica Park. Johnson, after two seasons of 50-plus saves for the Orioles, was torched in his first opportunity for the A's, who paid him $10 million on a one-year deal.

As for Robertson, there is a comfort in this role because it's with the only team he has known. And for a pitcher whose 11.71 K/9 ratio is the fourth-best in history (minimum 300 innings), the confidence seems to be there, too. The only thing stopping him before Thursday night had been the rest of the Yankees. The Astros were easy.

"I'm happy,'' he said, "just to get the first win."

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